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1.
Ocean citizenship describes a relationship between our everyday lives and the health of the coastal and marine environment. Through our everyday lives we affect, and are affected by, the marine and coastal environment in numerous ways. As such, individuals have a responsibility to make informed lifestyle choices to minimize this impact. In doing so, the actions of individuals can contribute to the amelioration of large-scale and seemingly insurmountable geographical problems. This article outlines the concept of ocean citizenship within the context of the public understanding of marine environmental issues. The article draws heavily on the experience of the National Maritime Museum as an important contributor to the development of ocean citizenship in the United Kingdom. Specifically, the Planet Ocean initiative will be examined, in which the Museum has adopted a multimodal approach to public engagement through exhibitions, educational resources, and specific research publications. The article concludes by highlighting the importance of geography in the development and sustainability of ocean citizenship.  相似文献   
2.
Wind power resources on the eastern U.S. continental shelf are estimated to be over 400 GW, several times the electricity used by U.S. eastern coastal states. The first U.S. developer proposes to build 130 large (40 story tall) wind turbines in Nantucket Sound, just outside Massachusetts state waters. These would provide 420 MW at market prices, enough electricity for most of Cape Cod. The project is opposed by a vigorous and well-financed coalition. Polling shows local public opinion on the project almost equally divided. This article draws on semistructured interviews with residents of Cape Cod to analyze values, beliefs, and logic of supporters and opponents. For example, one value found to lead to opposition is that the ocean is a special place that should be kept natural and free of human intrusion. One line of argument found to lead to support is: The war in Iraq is problematic, this war is “really” over petroleum, Cape Cod generates electricity from oil, therefore, the wind project would improve U.S. security. Based on analysis of the values and reasoning behind our interview data, we identify four issues that are relevant but not currently part of the debate.  相似文献   
3.
Findings are reported of the VALCOAST project that had as one of its research objectives to ascertain: (a) stakeholder willingness to participate and cooperate in coastal management (CM), given local and national CM practices; and (b) stakeholder assessment of the "accessibility" and "friendliness" of current CM processes. The project involved case studies and stakeholder interviews in Belgium, Greece, Spain, and the UK. Major findings include: (1) most stakeholders are willing to cooperate in three out of the four case areas, but not to the same extent; (2) the participating "officials" in the case studies are expecting the stakeholders to be less willing to cooperate than the latter indicate; (3) stakeholders in all case studies do not expect to be heard by those responsible for CM, find it difficult to learn about the relevant institutional arrangements, and consider the communication of the objectives and anticipated impacts of CM policies to be inadequate. It is concluded that the strong evidence of stakeholders' potential willingness to cooperate in local initiatives is very encouraging for a devolved, regional approach to European Union coastal management policies, provided that this potential is capitalized upon in such policy processes.  相似文献   
4.
ABSTRACT

A scientific consensus has recently emerged suggesting that the dominant twentieth century paradigm of solving transportation congestion problems by building more freeways failed. The legacy of the freeway construction era is clearly visible in polluted and congested cities worldwide. To battle these ills, planning academics have been promoting more sustainable built form aligned with dedicated public/active transport provision. Partly as a result of the push coming from academia, a number of cities have sought to remove their freeways and replace the freed up space with alternate transport infrastructure, such as streets and boulevards. To discern if the transportation planning profession is currently undergoing a paradigm shift or whether freeway removal is merely a temporary fad, we have conducted a systematic review of the literature. In this article, we unpack the underlying reasons which have led some cities to removing their freeways. Results reveal that a paradigm shift has arguably not yet taken place in transportation planning. While many cities are creating human-scale and active transport spaces, currently these spaces tend to coexist alongside freeways. American cities, which were once the pioneers of freeway construction, appear to be lagging behind cities in Europe and Asia in this respect. If the current pace of freeway removal continues, it may take a few decades before the transportation planners, politicians, policy makers, and communities adopt radically different norms, methods, and goals. However, a radical approach may need to be taken sooner given alarming global warming predictions.  相似文献   
5.
The IVHS architecture of the California PATH program organizes traffic into platoons of closely spaced vehicles. Platoons are formed and broken up by two longitudinal control maneuvers, the merge and the split. A third longitudinal maneuver, decelerate to change lane, allows a platoon switching from one lane to another to enter its new lane at a safe spacing and speed. The maneuvers, particularly the merge, can be potentially hazardous. In a merge, the cars in the trail platoon are moving faster than those in the lead platoon, while the gap separating the two platoons is smaller than usual. A sudden deceleration by the lead platoon could cause a high-speed collision. If the relative velocities of the merging platoons can be constrained so that they are guaranteed never to collide at a high relative velocity, the merge can be considered safe. A maximum safe velocity for the trail platoon can be found for any given spacing and lead-platoon velocity. This paper presents a merge maneuver in which the velocity of the trail platoon never exceeds the maximum safe velocity. The controller switches among several feedback control laws that keep the velocity of the trail platoon inside a safe region and within comfort limits on jerk and acceleration, under normal circumstances. This merge maneuver can be considered to be the fastest merge strategy mat does not violate bounds on safety and comfort. The controller is also more robust to changes in the vehicles' acceleration capability than those that use a desired open-loop trajectory

The control approach used for the merge maneuver can be applied to the other maneuvers to ensure that they never result in a collision. The switching controllers for the split and decelerate to change lane maneuvers that are safe and yield a more comfortable ride than those that track a timed trajectory are also presented.  相似文献   
6.
There has long been conflict over the degree to which railways should follow commercial or social investment criteria. This paper outlines the components of a comprehensive social cost‐benefit analysis of railway investment, and then describes the current approach in Britain. British Rail investment proposals are subject to a purely financial appraisal, although in the subsidized sectors of the railway this is subject to the proviso that a ‘broadly comparable’ level of service should be maintained. Local authorities and private operators are able to apply for a central government grant towards the cost of schemes they sponsor. But grant is only payable in respect of external benefits—that is, benefits other than to public transport users. Sponsors are also expected to seek contributions from private developers wherever possible. The difficulties to which this approach leads are discussed, and illustrated with two case studies of actual schemes. In one, it appears that failing to consider disbenefits to bus operators (and in turn to users of bus services) could lead to investments being undertaken which are not justified. In the other, a scheme which yields a high Net Present Value could not go ahead, in the form that we evaluated, because there is no way of recouping enough of the user benefits as revenue. Both are examples of the sort of distorting effect on decision‐making the current regime may have.  相似文献   
7.
This article reports on an integrated modeling exercise, conducted on behalf of the US Federal Highway Administration, on the potential for frequent automated transit shuttles (‘community transit’), in conjunction with improvements to the walking and cycling environment, to overcome the last-mile problem of regional rail transit and thereby divert travelers away from car use. A set of interlocking investigations was undertaken, including development of urban visualizations, distribution of a home-based survey supporting a stated-preference model of mode choice, development of an agent-based model, and alignment of the mode-choice and agent-based models. The investigations were designed to produce best-case estimates of the impact of community transit and ancillary improvements in reducing car use. The models in combination suggested significant potential to divert drivers, especially in areas that were relatively transit-poor to begin with.  相似文献   
8.

New transit capital expenditures are typically evaluated in isolation from the transit/transport systems to which they belong. Problems with reporting performance elements such as ridership and costs are discussed. A focus on evaluating the total transport systems impact of new transit project implementation is called for. On this basis, new US rail transit systems have generally performed poorly. Total transit ridership has generally shown only minimal improvements and, at times, has declined. Financial performance has been disappointing in most cases, particularly when understood in the context of the additional system costs imposed through the reconfiguration of bus networks to serve the new rail systems. Low-cost approaches to improving basic transit services can often be more effective than either rail or bus capital-based projects. An obsession with technology leads to the wrong questions being asked. We should instead start inquiry with the study of needs.  相似文献   
9.
介绍了机电一体化技术在机车和地铁制动控制中的应用,并分析了该技术的优点。  相似文献   
10.
This paper examines American attitudes about the role and structure of government and how those attitudes affect the safety potential of ICT-based road safety technologies. It examines these attitudes in the context of 3 current intelligent transportation systems (ITS) initiatives: IntelliDriveSM, active traffic management (ATM), and automated enforcement. It concludes that cultural attitudes have a strong influence on the acceptance of such systems, and provides suggestions for how such systems might be implemented successfully.  相似文献   
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